Toulouse, please ignore the many imbeciles we sadly have on PPRuNe these days. Most of them are spotty little planespotters or FS simulator "pilots". I'm afraid that I cannot help you with any factual details. In the absence, so far, of any expert pilot comments may I just say that there could have been a number of scenarios that could have taken place. From what you describe it would not as such have been an engine fire. If it had, I imagine that the engine would have been completely shut down and an immediate emergency return to the airport would have been made assisted by ATC. The fact that it took you up to 30 mins to get back would indicate that the engine in question was powered back as a precaution and a return single engine landing executed. Again, the emergency services would have been called out simply as a precaution. I agree with you that the whole episode would have been a little frightning but in fact not such a big deal for highly trained crew.